If you're looking to replace the stock AMD or Intel
heatsink, you've come to the right place - FrostyTech.
Processor manufacturers ship their CPUs
with good coolers generally, so you'll have to look carefully to find
a heatsink that boasts lower temperatures and less noise. Finding those qualities amongst
the sea of after market CPU coolers is a tricky task.
It doesn't help that PC hardware review sites rely on different heatsink benchmarking standards; some
test on a single old CPU, others on just an AMD or Intel
CPU, while a select few use custom synthetic thermal test platforms.
What you might not
realize is that heatsinks perform differently on AMD and Intel processors, due to the difference in heat outputs, and
the larger integrated heat spreader AMD utilizes. Whether synthetically tested or not, heatsinks should always be
tested on both CPU platforms for the best indication of performance.

In this
review Frostytech is testing out Xigmatek's new HDT-S983 heatsink, an innovative
thermal solution that employs sculpted & textured aluminum fins, and large
copper heatpipes that make direct contact with the CPU.

If you take
the Xigmatek HDT-S983 and look at the bottom you'll see an aluminum base with
three 8.5mm wide grooves cut deeply into it. Set snugly within each groove is an
8mm diameter copper heat pipe, which has been flattened so everything is
flush. Instead of using a bulky copper plate, Xigmatek use the superior
heat conducting capabilities of heat pipes to conduct heat away from the
core of an AMD or Intel processor. Three 8mm diameter copper heatpipes
transfer that heat rapidly to a large array of sculpted and textured thin
aluminum fins above.

In
addition, Xigmatek make certain concessions to noise reduction, like rubberized
fan supports and a fan whose speed varies in response to processor heat output.
We'll tell you if the HDT-S983 succeeds as a lower noise heatsink, but first
let's examine some of the techniques in play here.

First of all, Xigmatek Co. Ltd. is a two year old manufacturer that is
quickly making a name for itself through innovation and advancement of thermal
techniques. The Xigmatek
HDT-S983 heatsink FrostyTech is reviewing today is equipped with soft rubber
vibration absorbing fan posts, and a 92mm PWM fan that scales from
1200-2800RPM. The
heatsink is compatible with socket 775 Intel Pentium and Core 2 Duo CPUs, and
all socket 754/939/940/AM2+ AMD Athlon64 processors. The HDT-S983 stands 136mm
tall and retails for somewhere in the region of $45CDN ($45USD).

The
Xigmatek HDT-S983 heatsink ships with brackets for LGA775 and AMD K8 processors
(754/939/940/AM2 respectively). The Intel socket 775 clips use the standard
push-to-lock plastic clips that insert into the four motherboard holes around
the processor socket.

AMD Athlon64 processors on 754/939/940/AM2+ work with a
modified spring clip that attaches to the central lugs on the AMD heatsink
retention frame. A cam lever at one end of the clip applies pressure to the
heatsink base directly. The AMD clips works, but we find it a little flimsy and
prone to lateral bending.

A
molex-to-3pin fan power adaptor is also included for motherboards which cannot
accommodate 4-pin PWM style power connectors.

Base Finish and Flatness

Flipping a
heatsink over to inspect the business end is often a simple indicator of overall
cooler quality. More practically speaking, a heatsink is in many ways only as
effective as the contact it makes with the processor - the flatter and smoother
the better. Base finish is one of the criteria that Frostytech measure in the
course of evaluating heatsinks, and it involves two distinct aspects. Surface
Finish is the first; this is calculated with the aid of Surface Roughness
Comparator that has a cross section of common machine surface finishes and their
numerical surface roughness equivalents in microinches. The second is Surface
Flatness. This is tested with an engineers straight edge or proven flat
surface, in two axis.

The base of
the Xigmatek HDT-S983 heatsink has a surface roughness of ~32 microinches, which
is considered good. The
aluminum and copper portions of the base have a smooth sanded finish, and are
perfectly flat in the axis parallel to the heatpipes. In the other axis the
surface is generally quite flat, but the four components are not entirely flush
across the entire 34mm long interface area. In some places a heatpipe
stands a sliver higher. There are six small voids created where the copper
heatpipe interfaces with the aluminum block, these allow excess
thermal compound to evacuate itself from between the heatsink and
processor.

There are three aspects of the Xigmatek HDT-S983 heatsink's design which are
very innovative, let's have a look at them next...